Drilling, completion, and production of reservoir wells involves monitoring of various subsurface formation parameters. For example, parameters of reservoir pressure and permeability of the reservoir rock formations are often measured to evaluate a subsurface formation. Fluid may be drawn from the formation and captured to measure and analyze various fluid properties of a fluid sample. Monitoring of such subsurface formation parameters can be used, for example, to determine the formation pressure changes along the well trajectory or to predict the production capacity and lifetime of a subsurface formation.
Traditional downhole measurement systems sometimes obtain these parameters through wireline logging via a formation tester tool. A formation tester tool may alternatively be coupled to a drill string in-line with a drill bit (e.g., as part of a bottom hole assembly) and even a directional drilling subassembly. The drill string often includes one or more stabilizer(s) to engage a formation wall during drilling to substantially reduce or eliminate vibration, wandering, and/or wobbling of the drill bit and the drill string during drilling operations.
A typical formation tester tool engages a formation wall to obtain measurements of the subsurface formation parameters. Therefore, measurement instruments or probes used to generate the subsurface formation parameters are sometimes configured to protrude from the drill string sufficiently to engage the formation wall. The amount of protrusion from the drill string is typically sufficient for the probes to meet or extend beyond the diameter of the stabilizer, which is typically configured to engage or about to engage the formation wall.
In some systems, each time a drill bit is selected or adjusted to drill a particular diameter well, the formation tester tool may also need to be replaced. One motivation for replacing the formation tester tool may be that the tester tool comprises an integral stabilizer no longer suitable for drilling a well of the selected diameter. A new formation tester tool is selected having an integral, larger diameter stabilizer to engage the wall of the larger diameter well. The formation tester tool may also need to be replaced so that its measurement instruments or probes extend further and engage the wall of the larger diameter well. In these systems, a drilling operation often requires a plurality of different formation tester tools to accommodate any of a number of well diameters. This requirement affects, for example, the cost of the service delivery.